Method for surgically repairing a damaged ligament

ABSTRACT

An anterior cruciate ligament (ACL) surgical repair technique involves the use of a single femoral and tibial tunnel and an implant that separates and positions two distinct bundles. This allows for the surgeon to create a more anatomic reconstruction with a procedure that is less technically demanding, can be performed using a transtibial or anteromedial approach, minimizes tunnel widening, and decreases operative time. The result is a strong fixation option for soft tissue grafts, with circumferential graft compression at the aperture, high pull-out strength, and ease of use. The graft bundles are positioned in a more anatomic orientation through the above noted single femoral and tibial tunnel.

This application claims the benefit under 35 U.S.C. 119(e) of the filingdate of Provisional U.S. Application Ser. No. 61/158,994, entitledAnterior Cruciate Ligament Surgical Reconstruction Technique, filed onMar. 10, 2009 and of the filing date of Provisional U.S. ApplicationSer. No. 61/158,999, also entitled Anterior Cruciate Ligament SurgicalReconstruction Technique, filed on Mar. 10, 2009.

This application is also related to U.S. application Ser. No. 11/281,566entitled Devices, Systems, and Methods for Material Fixation, filed onNov. 18, 2005 and now issued as U.S. Pat. No. 7,651,528, to co-pendingU.S. application Ser. No. 11/725,981, entitled Devices, Systems, andMethods for Material Fixation, filed on Mar. 20, 2007, to co-pendingU.S. application Ser. No. 11/923,526, entitled Methods and Systems forMaterial Fixation, filed on Oct. 24, 2007, to co-pending U.S.application Ser. No. 12/437,020, entitled Manual Soft Tissue TensioningSystems and Methods, filed on May 7, 2009, to co-pending U.S.application Ser. No. 12/437,007, entitled Inserter for Soft Tissue orBone-to-Bone Fixation Device and Methods, filed on May 7, 2009, and toco-pending U.S. application Ser. No. 12/634,581, entitled Devices,Systems, and Methods for Material Fixation, filed on Dec. 9, 2009.

All of the above prior applications are commonly owned and hereinexpressly incorporated by reference, in their entirety.

BACKGROUND OF THE INVENTION

The present invention relates generally to devices, systems and methodsfor material fixation. More specifically, the present invention relatesto techniques that can be used to firmly hold a soft tissue or graftagainst bone tissue within a bone tunnel.

It is known that the anterior cruciate ligament (ACL) is comprised oftwo bundles, the anteromedial (AM) bundle and the posterolateral (PL)bundle. However, the traditional transtibial ACL reconstructionre-creates only the AM bundle, and recent data has shown that this maynot restore normal rotational knee kinematics. In order to address thisdeficiency in rotational stability, surgeons have developed techniquesto reconstruct both the AM and PL bundles of the ACL, comparing thedouble bundle reconstruction. These techniques, which require the toplacement of two tibial and two femoral tunnels, increase the complexityof the operation, and this may result in increased complications andcompromise revision surgery. In addition, the size of the tibialfootprint may be prohibitively small in some patients, making itdifficult to create two anatomic tunnels.

What is needed, therefore, are improved methods which do not require thecreation of multiple tibial and/or femoral tunnels to achieve placementof a double bundle tendon graft.

SUMMARY OF THE INVENTION

The present invention comprises techniques which utilize a new implantsystem to reconstruct the ACL. The inventive techniques have beencharacterized as a “single-tunnel, double-bundle ACL reconstruction”.This technique involves the use of a single femoral and tibial tunneland an implant that separates and positions two distinct bundles. Thisallows for the surgeon to create a more anatomic reconstruction with aprocedure that is less technically demanding, can be performed using atranstibial or anteromedial approach, minimizes tunnel widening, anddecreases operative time. The result is a strong fixation option forsoft tissue grafts, with circumferential graft compression at theaperture, high pull-out strength, and ease of use. The graft bundles arepositioned in a more anatomic orientation through the above noted singlefemoral and tibial tunnel.

More particularly, there is described a method for repairing a damagedligament surgically, which comprises a step of preparing a ligamentgraft to be inserted in place of the damaged ligament, wherein the graftcomprises an anteromedial (AM) bundle having a plurality of graftstrands and a posterolateral (PL) bundle having a plurality of graftstrands. The preparing step further includes a step of securing the endof each graft strand of both bundles using suture, and a step ofdoubling the graft over itself. This suture securing step preferablyincludes stitching the ends of each graft strand using a whip stitch.Another innovative feature of the invention is the preferred usage of afirst suture color to secure the graft strands of the AM bundle and asecond different suture color to secure the graft strands of the PLbundle.

A femoral implant, which comprises movable portions which may bedeployed to expand outwardly to engage adjacent bone, is selected tohave a size suitably compatible to the size of the prepared ligamentgraft. A tibial tunnel and a femoral socket are created, using wellknown prior art methods, for receiving the ligament graft.Advantageously, unlike in prior techniques for attempting to utilizedouble bundle grafts in a single tunnel approach, no additional steps ofwidening the tibial tunnel or femoral socket are required to accommodateeither the bulk of the graft bundles or interference fixation devicesare required.

Additional method steps include securing the graft strand bundles to thefemoral implant so that they extend proximally from both sides of theimplant, wherein the AM bundle extends along one side of the implant andthe PL bundle extends along an opposing side of the implant, andsecuring ends of the suture used to secure the graft bundles to aninsertion device in a manner as to ensure optimal anatomical placementof the AM and PL graft bundles. The femoral implant is inserted throughthe tibial tunnel and into the femoral socket to a desired depth,following which, the movable portions of the femoral implant aredeployed to expand outwardly into adjacent bone. The suture securingends are disengaged from the insertion device, the insertion device isreleased from the femoral implant and proximally withdrawn from thetibial tunnel. Then, the graft bundles are tensioned, and their properpositioning in the knee is ensured.

Advantageously, neither the femoral implant nor the tibial implantutilize interference fixation to secure the graft. The graft strandbundles are secured to the femoral implant by inserting them through anaperture extending through the implant. In a preferred approach, thestep of securing the ends of the suture to an insertion device comprisessecuring the ends of the suture extending from the AM bundle to one sideof the insertion device and the ends of the suture extending from the PLbundle the an opposing side of the insertion device. The step ofsecuring the ends of the suture to the insertion device compriseswrapping the suture about suture cleats disposed on the insertiondevice.

Another advantageous feature of the inventive methods comprises a stepof making a horizontal mark on the tendon bundles at an edge of thefemoral implant to serve as a depth indicator. Marks are also made onthe graft strands that represent the AM bundle on the both the implantend and the sutured end to assist in identification of the respective AMand PL bundles during the procedure.

Before the femoral implant is deployed, the grafts representing the AMbundle are positioned in a poster-superior position and the graftsrepresenting the PL bundle in an antero-inferior position prior todeploying the femoral implant.

The step of tensioning the graft bundles preferably further comprises astep of securing the suture ends extending from the AM bundle to oneside of a tensioning device and a further step of securing the sutureends from the PL bundle to an opposing side of the tensioning device, inorder to ensure that equal tension is applied to each graft.

The inventive method additionally comprises a step of inserting anddeploying a tibial anchor for securing the graft bundles in place withinthe tibial tunnel.

The invention, together with additional features and advantages thereof,may best be understood by reference to the following description takenin conjunction with the accompanying illustrative drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of an insertion device for inserting anddeploying a femoral implant;

FIG. 2 is an enlarged view of a portion of the distal end of theinserter of FIG. 1, showing the graft bundles to be anchored using theinventive techniques;

FIG. 3 is an enlarged view of a different portion of the distal end ofthe inserter of FIG. 1, again showing the graft bundles to be anchoredusing the inventive techniques;

FIG. 4 is a representation of the implant system as described herein asit is installed in a human knee;

FIG. 5 is a view illustrating soft tissue grafts as prepared using thetechniques of the present invention, after they have been passed throughthe orifices of the femoral implant;

FIG. 6 is an enlarged illustration of the femoral implant and graft asimplanted, with the knee in a flexed orientation;

FIG. 7 is an isometric view of the handle portion of the inserter ofFIG. 1;

FIG. 8 is an illustration of a step of deploying the implant under theinventive technique;

FIG. 9 is an illustration of a step subsequent to the step shown in FIG.8;

FIG. 10 is an illustration showing the sutures disengaged from thesuture cleats;

FIG. 11 is a view of the handle portion of the inserter of FIG. 7,showing a releasing step for releasing the inserter from the implant;

FIG. 12 is a view illustrating a first step in a sequence of orientingand tensioning the suture;

FIG. 13 is a view illustrating a second step in the sequence;

FIG. 14 is a view illustrating a third step in the sequence;

FIG. 15 is a view illustrating a fourth step in the sequence;

FIG. 16 is a view illustrating a step of inserting the tibial sheathinto the knee;

FIG. 17 is a view showing a step of inserting the tibial screw into thesheaths and tightening the screw; and

FIGS. 18 and 19 are views showing the installed tibial sheath.

DETAILED DESCRIPTION OF THE INVENTION

The present inventive technique is indicated for primary and revisionreconstruction of ACL deficient patients. The procedure should beconsidered for any patient with a pronounced pivot shift, and therefore,rotational instability. The inventive ACL reconstruction techniquesafford surgeons a strong fixation option for soft tissue grafts, withcircumferential graft compression at the aperture, high pull-outstrength, and ease of use. The graft bundles are positioned in a moreanatomic orientation through a single femoral and tibial tunnel.

Arthroscopy and Preparation

In accordance with the inventive techniques, the patient is positionedsupine on the operating table in the ACL position preferred by thesurgeon. A diagnostic arthroscopy is performed and concomitant pathologyis addressed. Diagnosis of ACL rupture is confirmed and the ACL remnantis derided. The center of the both the tibial and femoral footprints ofthe ACL are identified and marked with a thermal device prior tocomplete removal. These locations will serve as the center for thefemoral socket and tibial tunnel.

Graft Preparation

A hamstring autograft or allograft is recommended. Alternatively, iftibialis allograft (anterior or posterior) is used, one half of thegraft must be divided into two segments, each with an approximate widthof 6 mm. In the illustrated example, graft preparation is completedusing the Gracilis and Semitendinosis tendons.

Referring particularly to FIGS. 1-6, in FIG. 1 there is shown aninsertion device 10 which comprises a handle portion 12 and a distal endportion 14. A graft 16 is disposed about the distal end 14 of the device10. The graft 16 comprises an AM bundle 18 and a PL bundle 20. Both endsof both graft strands are secured, preferably with a #2 non-absorbablesuture in a whip-stitch fashion, as shown at 22 and 24, respectively. Ina preferred approach, different colored sutures are used to distinguishbetween the AM and PL bundles. For example, one end of theSemitendinosis Graft is stitched with a blue suture, and the other endwith a green suture. The same process is completed with the GracilisGraft.

Once the graft strands are stitched, the graft is doubled over itselfand measured with a sizing guide, such as a graft sizing block (notshown), trough which the graft bundles are pulled. Using a graft sizingblock, a diameter is selected through which the graft bundle fitstightly, but still passes through. An appropriately sized femoralimplant 26 is then selected, and each graft strand is mounted onto thefemoral implant 26, by inserting the strands through the implantaperture 28 as shown particularly in FIG. 5.

Tibial Tunnel Placement

A tibial tunnel 30 and femoral socket 32 (FIG. 4) are created in thetibia 33 a and femur 33 b, respectively, in the usual fashion. Aparticular advantage of the present invention, in contrast to priorapproaches, is that little or no modification, such as widening ornotching, of the otherwise usual tunnels need be performed. Thus, thetibial tunnel 30 is placed in the center of the tibial footprint. Thisis medial to the posterior aspect of the anterior horn of the lateralmeniscus. The guide pin for the tibial tunnel is placed immediatelyanterior to the MCL with the tibial guide set at 50 degrees, at aminimum of 3 cm distal to the joint. This medial starting point createsa more horizontal tibial tunnel, allowing placement of a femoral socketlower down the notch wall. The guide pin is drilled from this point tothe center of the ACL tibial footprint, on the medial third of theintercondylar plateau, in line with the posterior border of the anteriorhorn of the lateral meniscus. This guide pin is then over-drilled withthe appropriate sized cannulated reamer, typically 9 or 10 mm, aspreviously determined by the size of the graft.

Femoral Socket Placement

The femoral socket 32 is positioned in the center of the femoralfootprint, low on the femoral notch (two o'clock in a left knee, teno'clock position in a right knee). This location is typically accessiblewith an ACL over-the-top guide through the tibial tunnel. Alternatively,if this point is not accessible through the tibial tunnel, a lowantero-medial portal is employed. The guide pin for the femoral fixationdevice should be inserted to the cortex of the femur. Depth marks on theguide pin indicate the length of the femoral tunnel. After insertion ofthe guide pin, the pin is over-reamed with the appropriately sizedreamer, usually 9 or 10 mm, to a depth that permits femoral implantplacement (minimum 30 mm).

Graft Placement and Fixation

The distal end portion 14 of the insertion device 10 comprises a shaft34, to the distal end of which is secured the femoral implant 26, asshown in FIG. 5. The next step in the inventive procedure is to pass theprepared soft tissue double bundle grafts 16 through the orifice oraperture 28, as also shown in FIG. 5. Then, the sutures 36 of theprepared tendons 16 are wrapped around suture cleats 38 on the inserterhandle portion 12 (FIG. 1). To achieve optimal anatomical placement ofthe bundles, it is preferred that the like-colored, sutured graft endsrepresenting the AM bundle be wrapped on one suture cleat. The suturedends representing the PL bundle are wrapped on the opposite suturecleat. A horizontal mark 40 (FIG. 1) is made on the tendon bundles atthe inferior edge of the implant 26 to serve as the aperture depthindicator. By turning the inserter handle 12 over, with the safety pin42 facing down, additional marks 44 (FIG. 3) are made on the grafts thatrepresent the AM bundle at both the implant end and the sutured end.This helps with intra-articular and extra-articular identification ofthe bundles once inserted into the femoral tunnel.

The femoral fixation device 26 with the graft 16 properly positioned isinserted through the tibial tunnel 30 (or the AM portal if this was usedto create the femoral tunnel) into the femoral socket 32. This insertionstep is preferably done while holding the implant inserter handleportion 12 with the safety pin 42 in an upward facing orientation, andthe insertion step continues until the implant is moved distally intothe femoral socket to the marked depth location 40. This step isillustrated in FIG. 6. The device should be oriented so that one graftis positioned postero-superior (ten o'clock position in the left kneeflexed to 90 degrees) and one graft is antero-inferior (four o'clockposition in the left knee flexed to 90 degrees) to approximate anatomicorientation until the implant is seated. For the illustrated device,this is accomplished particularly, for the purpose of achieving optimalanatomic femoral placement of the graft bundles, by rotating theinserter, with the knee flexed to 90 degrees, until the marked graftsrepresenting the AM bundle are placed in the postero-superior positionand the PL bundles are placed in the antero-inferior position.Orientation of the suture cleats 38, located on the inserter handle 12,will be approximately 10 and 4 o'clock for a left knee.

The device is then deployed, providing for aperture femoral fixation.This is done by ensuring the implant is in proper position and thesafety pin 42 is completely pulled out of the handle 12, by pullingupwardly (FIG. 7). The release of the safety pin 42 permits a deploymentknob 46 to rotate.

With the inserter handle 12 held firmly in place, the implant deploymentknob 46 may be rotated (FIG. 8) in the direction of arrow 48, clockwise,until the deployment knob can no longer be turned, advancing distally tothe point that it comes into contact with the remaining portion of theinserter handle 12. This advanced position is shown in FIG. 9, whereinthe femoral implant is fully deployed, to engage expanded portions ofthe implant, which have been moved outwardly during the deploymentsequence, as shown, with adjacent bone.

Once the implant 26 is deployed, the sutures 36 are disengaged from thesuture cleats 38, as shown in FIG. 10. The inserter 10 is then releasedfrom the implant 26 by pulling proximally an implant release knob 50from the deployment knob 46, as illustrated in FIG. 11, and holding itin the retracted position. Next, the inserter handle 12 is drawn back.The inserter 12 is removed from the operative site and discarded.

A tendon expander or suture tensioning device 52 is held in anorientation generally perpendicular to the tibial tunnel (FIG. 12), andthe sutured ends 36 of the tendon bundles are wrapped around suturecleats 54 on either end of the tensioning device 52. This is done insuch a way that the sutures are first inserted into lateral slits 56(FIG. 13), and then wrapped around the vertical cleats 54. Thisprocedure is disclosed more fully in U.S. application Ser. No.12/487,020, already expressly incorporated herein by reference. Byanchoring the AM and PL bundles to opposite sides of the tensioner,equal tension is applied to each graft using this convenient one-handeddevice.

As shown sequentially in FIGS. 13-15, for proper orientation of thegraft bundles at the tibial aperture, the tensioner 52 is positioned, asnoted above, until the tendons representing the AM bundle are positionedin the anteromedial portion of the tunnel, and the PL bundle ispositioned in the posterolateral portion. Rotation occurs by holding theT-handle of the tensioner, with visualization of the tibial footprint,so that one graft limb is positioned in the anteromedial portion of thetunnel and one in the posterolateral portion. This process ofpositioning the bundles can be facilitated by inserting a flat device,such as a Freer elevator, into the tibial tunnel between the bundles torotate the graft at the internal aperture. Holding the bundles in thedesired orientation, the knee is then cycled with tension applied to thegraft.

Once this tensioning procedure has been completed, it is time to insertthe tibial sheaths and screw, with the sheaths being oriented so thatone bundle sits at the PL aspect of the tunnel and the other sits on theAM border. The knee is placed in full extension, and with the graftunder tension, the tibial sheaths 58 are inserted into the tibialtunnel, between the tendon bundles, such that cortical engagement tabs61 (FIGS. 18 and 19) on the sheaths are in the 9 o'clock position for aleft knee and 3 o'clock for a right knee. The sheaths should bepositioned so that the tabs 61 are fully seated against the tibia. Careis taken throughout this final procedure to maintain tension on thegraft with the tensioner 52 to prevent loss of graft tension. At thispoint, the sheath inserter 60 (FIG. 16) is snapped off, disengaged fromthe sheaths, and discarded.

At this juncture, a tibial screw 62, selected to be of a size to matchthe diameter of the tibial tunnel, is securely placed onto a distal endof a tibial inserter 64 (FIG. 17). The screw and inserter are insertedinto the tibial tunnel, through an aperture in the tensioning device 52,as shown in FIG. 17, so that the tibial screw is positioned in thecenter of the sheaths, with the tip of the screw engaging the sheaths.The inserter 64 is then turned clockwise until the screw head is flushwith the superior rim of the cortical wall. Because tibial screw threadsare designed to match those of the sheaths, excess torque is not neededto engage and insert the screw. As shown in FIGS. 18 and 19, once thetibial screw has been completely seated to the cortical wall, theinserter 64 is removed by pulling the handle straight back. Theintegrity of the repair is then checked, after which the excess suture36 and tendon is trimmed flush with the tibial tunnel.

Accordingly, although exemplary embodiments of the invention has beenshown and described, it is to be understood that all the terms usedherein are descriptive rather than limiting, and that many changes,modifications, and substitutions may be made by one having ordinaryskill in the art without departing from the spirit and scope of theinvention.

1. A method for repairing a damaged ligament surgically, comprising:preparing a ligament graft to be inserted in place of the damagedligament, wherein the graft comprises an anteromedial (AM) bundle havinga plurality of graft strands and a posterolateral (PL) bundle having aplurality of graft strands, the preparing step including a step ofsecuring the end of each graft strand of both bundles using suture, anda step of doubling the graft over itself; selecting a femoral implant,which comprises movable portions which may be deployed to expandoutwardly to engage adjacent bone, having a size suitable for the sizeof the prepared ligament graft; creating a tibial tunnel and a femoralsocket for receiving the ligament graft; securing the graft strandbundles to the femoral implant so that they extend proximally from bothsides of the implant, wherein the AM bundle extends along one side ofthe implant and the PL bundle extends along an opposing side of theimplant, the securing step including using a first suture color tosecure the graft strands of the AM bundle and using a second differentsuture color to secure the graft strands of the PL bundle; securing endsof the suture used to secure the graft bundles to an insertion device ina manner as to ensure optimal anatomical placement of the AM and PLgraft bundles; inserting the femoral implant through the tibial tunneland into the femoral socket to a desired depth; deploying the movableportions of the femoral implant to expand outwardly into adjacent bone;disengaging the suture securing ends from the insertion device;releasing the insertion device from the femoral implant and proximallywithdrawing the insertion device from the tibial tunnel; and tensioningthe graft bundles and ensuring their proper positioning in the knee. 2.The method as recited in claim 1, wherein the suture securing stepincludes stitching the ends of each graft strand using a whip stitch. 3.The method as recited in claim 1, wherein the creating step does notinclude a step of widening either the tibial tunnel or the femoralsocket so that they are substantially wider in one radial direction thananother.
 4. The method as recited in claim 1, wherein the creating stepdoes not include a step of creating notches in either the femoral socketor the tibial tunnel.
 5. The method as recited in claim 1, wherein thegraft strand bundles are secured to the femoral implant by insertingthem through an aperture extending through the implant.
 6. The method asrecited in claim 1, wherein the step of securing the ends of the sutureto an insertion device comprises securing the ends of the sutureextending from the AM bundle to one side of the insertion device and theends of the suture extending from the PL bundle the an opposing side ofthe insertion device.
 7. The method as recited in claim 6, wherein thestep of securing the ends of the suture to the insertion devicecomprises wrapping the suture about suture cleats disposed on theinsertion device.
 8. The method as recited in claim 1, and furthercomprising a step of making a horizontal mark on the tendon bundles atan edge of the femoral implant to serve as a depth indicator.
 9. Themethod as recited in claim 1, and further comprising a step ofpositioning the grafts representing the AM bundle in a poster-superiorposition and the grafts representing the PL bundle in an antero-inferiorposition prior to deploying the femoral implant.
 10. The method asrecited in claim 1, wherein the step of tensioning the graft bundlesfurther comprises a step of securing the suture ends extending from theAM bundle to one side of a tensioning device and a further step ofsecuring the suture ends from the PL bundle to an opposing side of thetensioning device, in order to ensure that equal tension is applied toeach graft.
 11. The method as recited in claim 1, and further comprisinga step of inserting and deploying a tibial anchor for securing the graftbundles in place within the tibial tunnel.
 12. A method for repairing adamaged ligament surgically, comprising: preparing a ligament graft tobe inserted in place of the damaged ligament, wherein the graftcomprises an anteromedial (AM) bundle having a plurality of graftstrands and a posterolateral (PL) bundle having a plurality of graftstrands, the preparing step including a step of securing the end of eachgraft strand of both bundles using suture, and a step of doubling thegraft over itself; selecting a femoral implant, which comprises movableportions which may be deployed to expand outwardly to engage adjacentbone, having a size suitable for the size of the prepared ligamentgraft; creating a tibial tunnel and a femoral socket for receiving theligament graft; securing the graft strand bundles to the femoral implantso that they extend proximally from both sides of the implant, whereinthe AM bundle extends along one side of the implant and the PL bundleextends along an opposing side of the implant; securing ends of thesuture used to secure the graft bundles to an insertion device in amanner as to ensure optimal anatomical placement of the AM and PL graftbundles; inserting the femoral implant through the tibial tunnel andinto the femoral socket to a desired depth; deploying the movableportions of the femoral implant to expand outwardly into adjacent bone;disengaging the suture securing ends from the insertion device;releasing the insertion device from the femoral implant and proximallywithdrawing the insertion device from the tibial tunnel; tensioning thegraft bundles and ensuring their proper positioning in the knee; andmaking marks on the graft strands that represent the AM bundle on theboth the implant end and the sutured end to assist in identification ofthe respective AM and PL bundles during the procedure.
 13. The method asrecited in claim 12, wherein the suture securing step includes stitchingthe ends of each graft strand using a whip stitch.
 14. The method asrecited in claim 12, wherein the creating step does not include a stepof widening either the tibial tunnel or the femoral socket so that theyare substantially wider in one radial direction than another.
 15. Themethod as recited in claim 12, wherein the creating step does notinclude a step of creating notches in either the femoral socket or thetibial tunnel.
 16. The method as recited in claim 12, wherein the graftstrand bundles are secured to the femoral implant by inserting themthrough an aperture extending through the implant.
 17. The method asrecited in claim 12, wherein the step of securing the ends of the sutureto an insertion device comprises securing the ends of the sutureextending from the AM bundle to one side of the insertion device and theends of the suture extending from the PL bundle the an opposing side ofthe insertion device.
 18. The method as recited in claim 17, wherein thestep of securing the ends of the suture to the insertion devicecomprises wrapping the suture about suture cleats disposed on theinsertion device.
 19. The method as recited in claim 12, and furthercomprising a step of making a horizontal mark on the tendon bundles atan edge of the femoral implant to serve as a depth indicator.
 20. Themethod as recited in claim 12, and further comprising a step ofpositioning the grafts representing the AM bundle in a poster-superiorposition and the grafts representing the PL bundle in an antero-inferiorposition prior to deploying the femoral implant.
 21. The method asrecited in claim 12, wherein the step of tensioning the graft bundlesfurther comprises a step of securing the suture ends extending from theAM bundle to one side of a tensioning device and a further step ofsecuring the suture ends from the PL bundle to an opposing side of thetensioning device, in order to ensure that equal tension is applied toeach graft.
 22. The method as recited in claim 12, and furthercomprising a step of inserting and deploying a tibial anchor forsecuring the graft bundles in place within the tibial tunnel.